1. Field of the Invention
This invention pertains to a self-contained underwater breathing apparatus (SCUBA) and more particularly to a device that is capable of supplying various oxygen/air mixtures to a diver in distress whether the diver is below or above the surface of the water.
2. General Background
The sport of underwater diving is enjoyed by both amateurs and professionals alike. With the advent of diving computers, the duration and depth of each dive are more accurately assessed thereby permitting sufficiently longer "bottom time" than was previously available using standard Navy Dive Tables. Unfortunately, however, because of this increase in "bottom time", the diver is subject to a greater risk of incurring decompression sickness and/or air embolism. This risk increases should the diver also be overweight, out of shape, smoke, or have other health problems.
Decompression sickness, or the "bends", results from an increase of nitrogen gas bubbles in the blood stream as a consequence of breathing pressurized air. It is important for these pressurized gas bubbles to be removed from the blood stream before the diver surfaces. If they are not removed, their expansion in the diver's tissue upon surfacing can result in symptoms ranging from mild discomfort in the joints to complete incapacitation. If this occurs, it becomes extremely important for the diver to be re-pressurized, such as in a decompression tank or chamber, so that as much of the pressurized nitrogen can be removed as possible. Unfortunately, however, relocation of the diver to such a decompression tank or chamber is time consuming thereby causing the stricken diver much discomfort. Also, by the time such a tank is located, permanent physical damage to the diver may have already occurred. Furthermore, even though it is becoming more common for large dive boats to be outfitted with such decompression tanks, just by bringing the diver to the surface will increase the diver's pain, discomfort, and possibility of injury.
Air embolism is caused by the rupture of lung tissue due to the rapid expansion of pressurized air should the diver surface too quickly. It is vitally important for the diver to fully exhale during surfacing so as to remove all such pressurized air from the lungs before any damage can occur. Thus, divers must surface at a rate sufficient enough to remove as much pressurized air from the body's tissue as possible. Consequently, it has become normal operating procedure for divers to surface in stages, staying at one level for a certain period of time before moving on to the next level, so as to give the body time to rid itself of any lingering gas bubbles.
It has been found that supplying a diver suffering from the bends with 100% oxygen helps reduce and/or eliminate the pressurized nitrogen gas bubbles. Additionally, 100% oxygen has also been found useful in resuscitation techniques for both drowning victims as well as those with lung damage. In fact, SCUBA instructors and dive boats are now frequently coming equipped with an emergency oxygen tank for just this purpose.
In the event a diver in distress is brought to the surface, oxygen must be supplied as quickly as possible. Generally, the oxygen tanks on the dive ship are not immediately available and their connecting mouthpiece is either stored with the tank or elsewhere. Thus, precious time may be wasted assembling the necessary apparatus before oxygen can be made available to the diver in distress.
Despite all the precautions taken, divers still contact the bends and become disabled via air embolism. Also, just by bringing the distressed diver to the surface can result in sever injury even though the dive boat contains all the currently available safety features. It is thus an object of the present invention to provide a means of supplying emergency oxygen to a diver in distress either above or below the surface of the water as needed. A further object of the invention is the ability to supply either 100% oxygen, a mixture of air/oxygen, or 100% air to the diver in distress as may be required. Thus, by being able to supply 100% oxygen to a diver in distress before surfacing, the magnitude and consequence of contacting the bends and/or air embolism is significantly reduced. Still another object of the present invention is to provide a means of supplying emergency gas directly to a face mask placed over the diver in distress or fitted to an unconscious victim. Yet another object of the present invention is the ability to supply such gas mixture below the surface of the water without endangering the rescuing diver or requiring his/her mouthpiece removal. These and other objects and advantages of this invention will become obvious upon further investigation.